JP4099772B2 - IP multicast switching control system, IP multicast switching control method, program for the same, and recording medium recording the program - Google Patents

Description

  The present invention relates to a technique for restricting multicast distributors when multicasting IP packets in an IP network, and in particular, switching time without receiving a multicast participation request received from a host for multicast packet flow switching control. The present invention relates to an IP multicast switching control system and an IP multicast switching control method.

  As a conventional IP multicast system, a multicast protocol is used to determine a route between a sender and a receiver by forwarding a reception request hop-by-hop. A method of determining a route by flooding is considered. Examples of the former include Non-Patent Documents 1 and 2, and examples of the latter include Non-Patent Documents 3 and 4.

  In the previously filed Japanese Patent Application No. 2003-297237 “IP multicast control method and apparatus” (hereinafter referred to as “prior application technology”), the present applicant, as shown in FIG. An IP multicast control technique in a system configuration including a host 300, a host accommodating router 400, a multicast relay router 500, and distribution servers 610 and 620 is proposed.

  In the prior application technique, as shown in the operation example of FIG. 19, the host accommodating router 400 has a function of monitoring the received multicast traffic for each IP multicast address and for each distribution source IP address. If no multicast traffic is received from the distribution server 610 for a certain period of time, it is determined that the traffic from the distribution server 610 has stopped, and a distribution source change request including the IP multicast address and the distribution source IP address that are no longer received Is transmitted to the distribution source database 100.

  The distribution source database 100 that has received the distribution source change request is a distribution server other than the distribution server IP address described in the distribution source change request among the distribution server IP addresses corresponding to the IP multicast address described in the distribution source change request. A response including the IP address of 620 is returned.

  The host accommodating router 400 that has received the response changes the distribution server IP address of the multicast distribution request to the distribution server IP address described in the response. The host accommodating router 400 receives the traffic of the IP multicast address from the distribution server 620 and distributes it to the host 300.

RFC2362 draft-ietf-pim-sm-v2-new-07 RFC1075 draft-ietf-pim-dm-new-v2-01

  However, in the prior application technique, since the switching control is triggered by a multicast participation request received from the host, there is a problem that a switching time almost equal to the time interval of the multi-participation request is required at the maximum.

  An object of the present invention is to provide an IP multicast switching control system and an IP multicast switching control method capable of reducing the switching time without solving the above-described problems and without being triggered by a multicast participation request received from a host by switching control. That is.

  In order to achieve the above object, the present invention uses the multicast output selection unit to autonomously select and output only the active system from the received multicast packet, thereby providing a multicast participation request timing from the host. Enables switching control autonomously by a host accommodating router that does not link.

  In this case, receiving both the active and standby traffic at the host accommodating router is effective for shortening the switching time.

  In addition to shortening the switching time, the host accommodating router autonomously sends a multicast participation request only to the active system asynchronously with the multicast participation request from the host. It is effective when using it efficiently.

  In addition, when the active system and the standby system are designated, it is effective in that the switching control is simplified by setting the priorities in advance and selecting according to the priorities.

  Furthermore, when setting priorities, it is possible to automatically detect the restoration of the original distribution server by making a multicast participation request to the highest-priority distribution server after a certain period of time has elapsed after switching due to a timer operation. It becomes.

  In addition, combining the method for selecting the active packet to be transmitted from the multicast packet being received and the method for selecting the request destination of the multicast participation request makes it possible to use both the host accommodating router and the distribution server accommodating router. To do. That is, for a distribution server that directly accommodates a multicast server that does not require a multicast participation request to the upstream router, a method of selecting an active packet to be transmitted from the received multicast packet is applied, and a multicast participation request to the upstream router is applied. It is effective to use a method for selecting a request destination of a multicast participation request for a remotely connected distribution server that is necessary.

Hereinafter, the configuration of the present invention will be described more specifically.
(1) An IP multicast switching control system having an IP multicast network, a host accommodating router connected to the IP multicast network, and a distribution server accommodating router, the host accommodating router corresponding to the IP multicast address and the IP multicast address A switching control table for storing a plurality of transmission source IP addresses, system information indicating whether each transmission source IP address is a working system or a standby system, and a reception state of a packet of each transmission source IP address, and the same IP multicast A means for selecting and outputting a multicast packet based on a source IP address and a means for monitoring a reception state of the multicast packet based on a source IP address, and the source IP address of the same IP multicast address is included in the switching control table. Less than one source IP address is stored as the active system, the other source IP address is stored as the standby system, and a means for monitoring the reception status of the multicast packet is stored in the IP header of the received multicast packet. Obtaining the information of the IP multicast address and the source IP address, and storing in the switching control table whether the combination of the IP multicast address and the source IP address is being received or not received; If the active system stored in the switching control table has not been received for a predetermined time, the source IP address is switched to the standby system, and the source IP address of the original standby system is receiving A means for switching one of the transmission source IP addresses to the active system and selectively outputting a multicast packet refers to the switching control table, Of one IP multicast address of the packet, and outputs only the packets of the primary system transmission source IP address.

(2) In the above (1), the switching control table stores the priority order of each source IP address instead of storing whether each source IP address is the active system or the standby system, and selectively outputs a multicast packet. The means refers to the switching control table and outputs only the packet of the source IP address having the highest priority among the packets received with the same IP multicast address.

(3) In the above (1), the host accommodating router is provided with means for selectively issuing a multicast participation request to an upstream device instead of means for selectively outputting a multicast packet, and means for selectively issuing the multicast participation request includes: By referring to the switching control table, means for issuing a multicast participation request only to the working source IP address and monitoring the reception status of the multicast packet monitors the reception of the working packet, and the working packet Is not received within a predetermined time period, the current working system of the switching control table is switched to the standby system, and one source IP address of the original standby system is switched to the working system, and the switching control table When switching occurs in the network, a means for selectively issuing a multicast participation request is available for the active system after switching. Sending a multicast join request.

(4) In the above (2), the host accommodating router includes means for selectively issuing a multicast participation request instead of means for selecting and outputting the multicast packet, and the means for monitoring the reception state of the multicast packet includes the multicast participation request. The packet reception of the source IP address that issued the packet is monitored, and when the packet is not received within a predetermined time, the next highest priority source IP address is used in the switching control table. When switching to the system and switching occurs in the switching control table, the means for selectively issuing a multicast participation request transmits the multicast participation request to the active system after switching. An IP multicast switching control system.

(5) In the above (4), when the host accommodating router has a timer and switches to the source IP address that issues the multicast participation request, if the priority of the source IP address before switching is the highest, switching is performed. The timer is started for the packet of the previous transmission source IP address, and after a predetermined time elapses, a multicast participation request is issued to the transmission source IP address before switching, and the packet of the transmission source IP address before switching is received. In this case, the source IP address that issues the multicast participation request is returned to the pre-switching source IP address.

(6) In the above (4), when the host accommodating router has a timer and switches to the source IP address that issues the multicast participation request, the source IP address before switching is more than the source IP address after switching If the priority is high, the timer is started for the packet of the transmission source IP address before switching, and a multicast participation request is issued to the transmission source IP address before switching after a predetermined time elapses. When the packet of the transmission source IP address is received, the transmission source IP address for issuing the multicast participation request is returned to the transmission source IP address before switching.

(7) In the above (5), the host accommodating router includes means for selecting and outputting the multicast packet, and the means for monitoring the reception state of the multicast packet is the IP multicast address and the source IP address from which the multicast participation request is issued If the priority of the source IP address is the highest in the IP multicast address when the packet is not received within a predetermined period of time, in addition to the source IP address, When the means for issuing a multicast participation request to the priority source IP address and monitoring the reception of the multicast packet receives multicast packets of a plurality of source IP addresses for the same IP multicast address, Select and output multicast packets It means, among the source IP address of the received packet, priority selects and outputs the highest packet priority stops multicast join request to the source IP address other than the highest.

(8) In the above (6), the host accommodating router is provided with means for selecting and outputting a multicast packet. If the source IP address before switching is higher in priority than the source IP address after switching, switching is performed. A means for issuing a multicast participation request to the previous source IP address and the post-switch source IP address, and monitoring the reception of the multicast packet sends a multicast packet of a plurality of source IP addresses to the same IP multicast address. When received, the means for selecting and outputting the multicast packet selects and outputs only the highest priority packet among the source IP addresses of the received packet, and the priority order among the source IP addresses of the received packet. Multicast participation required for a source IP address other than the highest IP address A stop.

(9) The IP multicast switching control system of (1) and the IP multicast switching control system of (3) are used in combination.

(10) An IP multicast switching control system characterized by using the IP multicast switching control system according to (2) above and the IP multicast switching control system according to any of (4) to (8) above.

(11) In any of (3) to (8) above, when the host accommodating router receives a multicast participation request designating an IP multicast address and a source IP address from the host, the source designated by the host Within the range of IP addresses, only packets with a source IP address having the highest priority in reception are output.

(12) In any one of the above (1), (2), (9), or (10), the means for selecting and outputting the multicast packet uses an IP multicast address to be output using a packet filter provided in the packet receiver. Only the combination of the source IP address is set for forwarding, and the other combinations of the IP multicast address and the source IP address are set as the blocking setting.

(13) An IP multicast network, a host accommodating router and a distribution server accommodating router connected to the IP multicast network, and the host accommodating router has an IP multicast address and a plurality of source IPs corresponding to the IP multicast address Among the packets of the same IP multicast address, the address, the system information indicating whether each source IP address is the active system or the standby system, and the switching control table that stores the reception status of the packet of each source IP address, An IP multicast switching control method in an IP multicast switching control system comprising means for selectively outputting a multicast packet based on a source IP address, and means for monitoring the reception state of the multicast packet. A step of storing only one transmission source IP address as the active system among the transmission IP addresses of the IP multicast address, and storing other transmission source IP addresses as the standby system, and means for monitoring a reception state of the multicast packet The information of the IP multicast address and the source IP address recorded in the IP header of the received multicast packet is acquired, and whether or not the combination of the IP multicast address and the source IP address is being received in the switching control table. A step of storing whether it is received, and when the active system stored in the switching control table has not been received for a predetermined time, the source IP address is switched to the standby system, Of the source IP addresses, one of the source IP addresses being received is switched to the active system. -Up and, means for selecting and outputting the multicast packet, referring to the switching control table, among the same IP multicast address of the packet, comprising the step of outputting the packets only working system source IP address.

(14) In the above (13), the switching control table stores the priority order of each source IP address instead of storing whether each source IP address is the active system or the standby system; The means for selectively outputting the multicast packet has a step of referring to the switching control table and outputting only the packet of the source IP address having the highest priority among the packets of the same IP multicast address being received.

(15) In the above (13), the host accommodating router includes means for selectively issuing a multicast participation request to an upstream device instead of means for selectively outputting a multicast packet, and means for selectively issuing the multicast participation request includes: A step of issuing a multicast participation request only to the source IP address of the active system with reference to the switching control table, and means for monitoring the reception state of the multicast packet monitor the reception of the active system packet, and the active system Switching the current working system in the switching control table to the standby system and switching one source IP address of the original spare system to the working system when the packet is not received within a predetermined time period. When a switch occurs in the switch control table, a multicast participation request is selectively issued. It means, comprising sending a multicast join request to the working system after switching.

(16) In the above (14), the host accommodating router includes means for selectively issuing a multicast participation request instead of means for selecting and outputting the multicast packet, and the means for monitoring the reception state of the multicast packet includes the multicast participation request. The packet reception of the source IP address that issued the packet is monitored, and when the packet is not received within a predetermined time, the next highest priority source IP address is used in the switching control table. A step of switching to a system, and a means for selectively issuing a multicast participation request when a switch occurs in the switching control table, and a step of transmitting a multicast participation request to the active system after switching.

(17) An IP multicast network, an IP multicast address connected to the IP multicast network, a plurality of source IP addresses corresponding to the IP multicast address, and whether each source IP address is an active system or a standby system In an IP multicast switching control system comprising: a host accommodating router having a switching control table for storing the system information of each and a reception state of a packet of each source IP address; and a distribution server accommodating router connected to the IP multicast network An IP multicast switching control program executed by the host accommodating router, wherein only one source IP address among the source IP addresses of the same IP multicast address is stored in the switching control table as the active system, and the like Sending The process of storing the original IP address as a standby system, the information of the IP multicast address and the source IP address written in the IP header of the received multicast packet is acquired, and the IP multicast address and the source are stored in the switching control table. A process for storing whether a combination of IP addresses is being received or not received, and if the active system stored in the switching control table has not been received for a predetermined time, the source IP Switch the address to the standby system, refer to the process of switching one of the source IP addresses being received to the active system among the source IP addresses of the original standby system, and the switching control table, and The process of outputting only the packet of the working source IP address out of the packets is sent to the host accommodating router. IP Multicast switching control program for causing the row.

(18) A computer-readable recording medium on which the IP multicast switching control program according to (17) is recorded.

  According to the present invention, the multicast packet flow can be switched in a short time, and the multicast reliability is improved.

  Embodiments of the present invention will be described in detail with reference to the drawings.

Example 1
Embodiment 1 of the present invention will be described in detail with reference to the drawings.
1 is a diagram illustrating a system configuration example according to the first embodiment of the present invention, FIG. 2 is a diagram illustrating a configuration example of a switching control table used in the first embodiment, and FIG. 3 illustrates an operation example according to the first embodiment. FIG.

  As shown in FIG. 1, the network configuration example of the first embodiment includes a host accommodating router 1, an IP network 2, distribution server accommodating routers 3 and 4, distribution servers 5 and 6, and a host 7. .

  The host accommodating router 1 includes a switching control unit 11, a multicast reception state monitoring unit 12, and a multicast selection output unit 13. The switching control unit 11 has a switching control table 111.

  In this description, the case where there are two distribution server accommodating routers and two distribution servers has been described, but this is for clarification of explanation, and the same applies to three or more distribution server accommodating routers and distribution servers. It is not intended to limit the invention. Further, in this description, the case where the number of hosts is one has been described. However, this is also the case with two or more for clarity of explanation, and the number of hosts does not limit the present invention.

Next, a configuration example of the switching control table 111 in the present embodiment will be described with reference to FIG.
The switching control table 111a according to the first embodiment is provided in the switching control unit 11, and includes an IP multicast address, a transmission source IP address, a reception state, and a switching system.

  Here, the IP multicast address, transmission source IP address, reception state, and switching system in the present invention will be described.

(A) “IP multicast address” is described in the destination address of the multicast packet, and is described as G1 in this description, for example.
(B) “Source IP address” refers to the IP addresses of distribution server 1 (5) and distribution server 2 (6). For example, in this description, the IP address of distribution server 1 (5) is S1, the distribution server The IP address of 2 (6) is denoted as S2.

(C) “Reception state” indicates whether reception is in progress or not reception based on the IP multicast address and the source IP address information monitored by the multicast reception state monitoring unit 12.
(D) “Switching system” indicates whether the combined traffic of the IP multicast address and the source IP address is the active system or the standby system.

  The multicast selection output unit 13 refers to the switching control table 111 and outputs only the active traffic to the host 7. Specifically, as shown in FIG. 2, for the packet whose destination address is the IP multicast address G1, only the packet in which the transmission source IP address of the distribution server 1 (5) as the active system is written And the packet in which the transmission source IP address of the distribution server 2 (6) as the standby system is written is blocked.

Next, a switching operation example of the first embodiment will be described with reference to FIG.
First, it is assumed that (S1, G1) is the active system and (S2, G1) is the standby system before switching. Here, (S1, G1) means that the IP multicast address is G1 and the source IP address is S1. In this case, the multicast selection output unit 13 transfers the packet (S1, G1) (s1, s2) and blocks the packet (S2, G1) (s3, s4).

  When the multicast reception monitoring unit 12 detects that the packet (S1, G1) has not been received (s5), the switch control unit 11 is notified of the packet reception of (S1, G1) (s6), and the table 111 of the switch control unit 11 is displayed. Rewrites (S1, G1) to not received (s7).

  As a packet non-reception detection method, a method of confirming whether or not a packet of (S1, G1) has arrived within a certain fixed time by using a timer can be considered. However, the detection method of a packet not received does not limit the present invention.

  The multicast selection output unit 13 refers to the switching control table 111a (s8), blocks the packet (S1, G1), and transfers the packet (S2, G1) (s9 to s11). Alternatively, when a change in the switching system occurs in the switching control table 111, the switching control unit 11 notifies the multicast selection output unit 13 of a change in switching from the current system of G1 to S2, and the multicast selection output unit 13 It is also possible to block the packet (S1, G1) and transfer the packet (S2, G1) (s9 to s11).

(Example 2)
Next, Embodiment 2 of the present invention will be described with reference to the drawings.
4 is a switching control table configuration example 111b used in the second embodiment, and FIG. 5 is a diagram illustrating an operation example of the second embodiment. The system configuration example is the same as that of the first embodiment (see FIG. 1).

  First, a configuration example of the switching control table 111 provided in the switching control unit 11 will be described with reference to FIG. The configuration example of the switching control table 111b according to the second embodiment is different in that the priority order is stored instead of the switching system according to the first embodiment.

Next, a switching operation example of the second embodiment will be described with reference to FIG.
First, in the state before switching, (S1, G1) has first priority, and (S2, G1) has second priority. In this case, the multicast selection output unit 13 transfers the packet (S1, G1) (s12, s13) and blocks the packet (S2, G1) (s14, s15).

  When the multicast reception monitoring unit 12 detects that the packet of (S1, G1) has not been received (s16), the switch control unit 11 is notified of the reception of the packet of (S1, G1) (s17), and the switching control unit 11 (S1 , G1) is rewritten to not received (s18).

  The multicast selection output unit 13 refers to the switching control table 11 (s19), blocks the unreceived packet (S1, G1), and forwards the packet (S2, G1) that is being received and has the next priority. (S20, s21).

(Example 3)
Next, Embodiment 3 of the present invention will be described with reference to the drawings.
6 is a system configuration example of the third embodiment, FIG. 7 is a configuration example of a switching control table used in the third embodiment, and FIG. 8 is a diagram illustrating an operation example of the third embodiment.

  The system configuration example of the third embodiment is the same as the configuration of the first embodiment except for the host accommodating router 1. Only the configuration of the host accommodating router 1 is different. In the present embodiment, the host accommodating router 1 includes a switching control unit 11 having a switching control table 111, a multicast reception state monitoring unit 12, and a multicast participation request selection output unit 13.

  As shown in FIG. 7, the switching control table 111b used in the third embodiment does not need to store a reception state as compared to the switching control table 111a in FIG.

Next, an operation example of the third embodiment will be described with reference to FIG.
First, it is assumed that (S1, G1) is an active system, and (S2, G1) and (S3, G1) are standby systems before switching. In this case, the multicast participation request selection output unit 14 transmits a multicast participation request to (S1, G1) (s22), and receives the multicast participation request to the distribution server accommodating router 1 (3) accommodated in the distribution server S1. Then, the multicast packet of (S1, G1) is transmitted to the host accommodating router 1 (s23).

In addition, the multicast reception monitoring unit 12 monitors packet reception of (S1, G1).
When the multicast reception monitoring unit 12 detects that the packet (S1, G1) has not been received (s24), the multicast reception monitoring unit 12 notifies the switching control table 111b that (S1, G1) has not been received (s25).

  The switching control unit selects (S2, G1) from the standby system for the table 111b and changes it to the active system (s26), and requests the multicast participation request selection output unit 14 to switch (s27). At this time, (S1, G1) is changed to the standby system.

  The multicast participation request selection output unit 14 that has received the switching request stops the multicast participation request for (S1, G1) and starts transmitting the multicast participation request for (S2, G1) (s28).

  The switching control unit 11 requests the multicast reception monitoring unit 12 to change the packet monitoring from (S1, G1) to (S2, G1) (s29), and the multicast reception monitoring unit 12 sets the monitoring target to (S1 , G1) to (S2, G1) (s30).

  The multicast participation request selection output unit 14 transmits a multicast participation request to (S2, G1) (s31), receives the multicast participation request in the distribution server accommodating router 2 (4) accommodated in the distribution server S2, The multicast packet of S2, G1) is transmitted to the host accommodating router 1 (s32).

  Further, if (S2, G1) is not received, the current system is changed from (S2, G1) to (S3, G1) in the same manner as the operation of switching (S1, G1) to (S2, G1) described above. Then, the same processing is performed.

Example 4
Next, a fourth embodiment of the present invention will be described with reference to the drawings.
FIG. 9 is a switching control table configuration example 111c used in the fourth embodiment, and FIG. 10 is a diagram illustrating an operation example of the fourth embodiment. The system configuration example of the fourth embodiment is the same as that shown in FIG. The configuration example of the switching control table 111c is almost the same as that in FIG. 4 except that the reception state is unnecessary.

Next, an operation example of the fourth embodiment will be described with reference to FIG.
The operation example of the fourth embodiment is the same as the operation example of the third embodiment, except that the priority order is stored in the switching control table 111c.

  First, (S1, G1) is the first priority, (S2, G1) is the second priority, and (S3, G1) is the third priority. In this case, the multicast participation request selection output unit 14 transmits a multicast participation request to (S1, G1) (s33), and receives the multicast participation request to the distribution server accommodating router 1 (3) accommodated in the distribution server S1. Then, the multicast packet of (S1, G1) is transmitted to the host accommodating router (s34).

  When the multicast reception monitoring unit 12 detects that the packet (S1, G1) has not been received (s35), the multicast reception monitoring unit 12 notifies the switching control unit 11 that the packet has not been received (S1, G1) (s36).

  When the switching control unit 11 is notified that (S1, G1) has not been received, the switching control unit 11 refers to the switching control table, and outputs a switching request to the second priority (S2, G1) corresponding to G1 by multicast participation request selection output. The multicast participation request selection output unit 14 stops the multicast participation request for (S1, G1) and starts transmitting the multicast participation request for (S2, G1) (s38).

  The switching control unit 11 requests the multicast reception monitoring unit 12 to change the packet monitoring from (S1, G1) to (S2, G1) (s39), and the multicast reception monitoring unit 12 sets the monitoring target to (S1 , G1) to (S2, G1) (s40).

  The multicast participation request selection output unit 14 transmits a multicast participation request to (S2, G1) (s41), receives the multicast participation request in the distribution server accommodating router 2 (4) accommodated in the distribution server S2, ( The multicast packet of S2, G1) is transmitted to the host accommodating router 1 (s42).

  In this way, if (S2, G1) is also not received, the third priority (S3, G1) is switched. The same applies when the fourth priority or later is set.

(Example 5)
Next, Embodiment 5 of the present invention will be described with reference to the drawings.
FIG. 11 is a diagram illustrating an operation example of the fifth embodiment. The system configuration example and the switching control table configuration example in the fifth embodiment are the same as those in the fourth embodiment.

  As shown in FIG. 11, in the fifth embodiment, the switching control unit 11 includes a timer, and when a switching notification from (S1, G1) to (S2, G2) is transmitted to the multicast participation request selection output unit 14. If the priority order of (s43) and (S1, G1) is the highest, a timer corresponding to (S1, G1) is started (s44), and a monitoring change is transmitted to the multicast reception monitoring unit 12 (s45).

  If the timer has timed out (s46), a notification of switching back from (S2, G1) to (S1, G2) is transmitted to the multicast participation request selection output unit 14 (s47).

  The multicast participation request selection output unit 14 that has received the switchback request stops the multicast participation request for (S2, G1) and starts transmitting the multicast participation request for (S1, G1) (s48).

  The multicast participation request selection output unit 14 transmits a multicast participation request to (S1, G1) (s49), receives the multicast participation request in the distribution server accommodating router 1 (3) accommodated in the distribution server S1, ( The multicast packet of S2, G1) is transmitted to the host accommodating router 1 (s50).

(Example 6)
Next, a sixth embodiment of the present invention will be described.
The sixth embodiment of the present invention is different from the fifth embodiment in that the timer is started.
In the sixth embodiment, when the switching notification from (S1, G1) to (S2, G2) is transmitted, if the priority order of (S1, G1) is higher than the priority order of (S2, G2), The timer corresponding to (S1, G1) is started. Other operations are the same as those in the fifth embodiment.

(Example 7)
Next, Embodiment 7 of the present invention will be described with reference to the drawings.
FIG. 12 is a diagram illustrating a system configuration example of the seventh embodiment, and FIG. 13 is a diagram illustrating an operation example of the seventh embodiment. The system configuration example of the seventh embodiment is different from the third embodiment in that a multicast output selection unit 13 is added to the host accommodating router 1 of FIG.

  In the operation example of the seventh embodiment, as shown in FIG. 13, when the switching control unit 11 is notified of non-reception of (S1, G1) (s51, s52), the switching control table 111 is referred to (S1 , G1) is the highest priority, a request to start (S2, G1) is made instead of a switch request from (S1, G1) to (S2, G1) as in the fifth embodiment (s53). .

  Upon receiving the start request, the multicast participation request selection output unit 14 transmits a multicast participation request to (S2, G1) in addition to (S1, G1) (s54, s55). In this embodiment, unlike the fifth embodiment, no timer is used.

  For example, while the distribution server S1 is out of order and (S1, G1) is not received, only (S2, G1) is received and distributed to the host (s56) as in the fifth embodiment. However, when the distribution server S1 is recovered, the host accommodating router receives both the packets (S1, G1) and (S2, G1) (s57).

  When receiving the packet (S1, G1) (s58), the multicast reception monitoring unit 12 notifies the switching control unit (s59).

  When the switching control unit 11 is notified of the reception of (S1, G1), the switching is set in the multicast selection output unit (s60) for the low priority (S2, G1), and the multicast participation request selection output unit 14 (s61), the transmission of the multicast participation request for (S2, G1) is stopped (s62), and only the transmission of the multicast participation request for (S1, G1) is made (s63). Further, the switching control unit 11 requests the multicast reception monitoring unit 12 to stop (S2, G1) (s64), and stops the reception monitoring for (S2, G1) (s65).

(Example 8)
Next, an eighth embodiment of the present invention will be described.
In the eighth embodiment of the present invention, the start request is different from the seventh embodiment. In the eighth embodiment, when the switching control unit 11 is notified from the multicast reception monitoring unit 12 that (S1, G1) has not been received, the priority order of (S1, G1) is higher than the priority order of (S2, G1). If it is also high, a start request is made to (S2, G1). If the priority order of (S1, G1) is lower than (S2, G1), a switching request from (S1, G1) to (S2, G1) is made. Other operations are the same as those in the seventh embodiment.

Example 9
Next, Embodiment 9 of the present invention will be described with reference to the drawings.
The system configuration of the ninth embodiment is the same as that of FIG.
FIG. 14 is a diagram illustrating the switching control table 111e according to the ninth embodiment.

  In the ninth embodiment, the operation method is registered for each source IP address in FIG. 7 as a first configuration example. The operation method is the method of the first embodiment or the method of the third embodiment. In FIG. 14, the system of the first embodiment is expressed as a traffic selection system, and the system of the third embodiment is expressed as a Join selection system.

  As a second configuration example, the configuration is the same as that in FIG. 7, and the traffic selection method is used if the source IP address is directly accommodated without registering the method, and the source IP address is directly accommodated. If it is not an IP address, it is possible to automatically select the Join selection method.

  The operation example of the ninth embodiment is the same as the operation example of the first embodiment for the traffic selection source IP address, and the operation of the third embodiment for the join selection source IP address. Similar to the example.

(Example 10)
Next, a tenth embodiment of the present invention will be described with reference to the drawings.
The system configuration of the tenth embodiment is the same as that of the seventh embodiment shown in FIG. FIG. 15 is a diagram illustrating the switching control table 111f used in the tenth embodiment.

  In the tenth embodiment, in addition to FIG. 9 as the first configuration example, the operation method is registered for each source IP address. The operation method is the method of the first embodiment or the method of the third embodiment. In FIG. 14, the system of the first embodiment is a traffic selection system, and the system of the third embodiment is a join selection system.

  Alternatively, as a second configuration example, if the source IP address is directly accommodated without registering the method, the traffic selection method is used. If the source IP address is not directly accommodated, Join A selection method and automatic selection are also conceivable.

  The operation example of the tenth embodiment is the same as the operation example of the second embodiment for the source IP address of the traffic selection method, and is implemented from the fourth embodiment for the source IP address of the join selection method. This is the same as the operation example of any of Example 8.

(Example 11)
Next, Example 11 of the present invention will be described with reference to the drawings.
The system configuration of the eleventh embodiment of the present invention is the same as the configuration of the seventh embodiment shown in FIG.
FIG. 16 is a diagram illustrating an operation example of the eleventh embodiment.

  In the eleventh embodiment, a protocol capable of requesting a plurality of source IP addresses for one IP multicast address between the host 7 and the host accommodating router 1 is used. For example, IGMP version 3 and MLD version 2 are conceivable.

  When the host accommodating router 1 receives a multicast participation request in which a plurality of transmission source IP addresses are described, the host accommodating router 1 refers to the switching control table 111 and the multicast output selection unit 13 only transmits the packet of the transmission source IP address that is the active system. To the host.

  For example, in FIG. 16, when the host accommodating router 1 receives a multicast participation request of S1, S2, and S3 from the host 7 to G1, (s66), if the active system for G1 is S1 (S1, G1) Are transferred (s67, s68).

  When the working system for G1 is changed to S2 (s69), only the packet of S2 which is the working system after the change is transferred (s71, s72).

(Example 12)
Next, Example 12 of the present invention will be described with reference to the drawings.
FIG. 17 is a diagram showing an operation example of Embodiment 12 of the present invention.
As shown in the figure, for example, when the working system is S1 and the standby systems are S2 and S3 for the IP multicast address G1, the host accommodating router 1 sends the destination IP address to the received packet filter means (S73). A packet whose address is G1 and whose source IP address is S1 is transparently set, and a packet whose destination IP address is G1 and whose source IP address is other than S1 is set to be blocked (s74, s75). As a result, for G1, the packets of S2 and S3, which are backup systems, are blocked (s76 to s79).

  Next, when the switching control unit 11 switches the active system from S1 to S2, the setting is changed with respect to the received packet filter means, and the packet whose destination IP address is G1 and whose source IP address is S2 is transmitted. The packet is set so that the destination IP address is G1 and the source IP address is other than S2 is set to be blocked (s80 to s86).

  The processing performed by the host accommodating router described above can be program-coded and recorded on a computer-readable recording medium and distributed, or distributed to users via a network such as the Internet.

It is a figure which shows the system configuration example of Example 1 of this invention. It is a figure which shows the example of a switching control table structure of Example 1 of this invention. It is a figure which shows the operation example of Example 1 of this invention. It is a figure which shows the example of a switching control table structure of Example 2 of this invention. It is a figure which shows the operation example of Example 2 of this invention. It is a figure which shows the system configuration example of Example 3 of this invention. It is a figure which shows the example of a switching control table structure of Example 3 of this invention. It is a figure which shows the operation example of Example 3 of this invention. It is a figure which shows the example of a switching control table structure of Example 4 of this invention. It is a figure which shows the operation example of Example 4 of this invention. It is a figure which shows the operation example of Example 5 of this invention. It is a figure which shows the system configuration example of Example 7 of this invention. It is a figure which shows the operation example of Example 7 of this invention. It is a figure which shows the example of a switching control table structure of Example 9 of this invention. It is a figure which shows the example of a switching control table structure of Example 10 of this invention. It is a figure which shows the operation example of Example 11 of this invention. It is a figure which shows the operation example of Example 12 of this invention. It is a figure which shows the system structural example of a prior application technique. It is a figure which shows the operation example of a prior application technique.

Explanation of symbols

1: Host accommodating router 2: IP network 3: Distribution server accommodating router 1
4: Distribution server accommodating router 2
5: Distribution server 1
6: Distribution server 2
7: Host 8: Distribution server accommodating router 3
9: Distribution server 3
11: Switching control unit 111 (111a to 111f): Switching control table 12: Multicast reception state monitoring unit 13: Multicast selection output unit 14: Multicast participation request selection output unit 100: Distribution source database 200: Authentication server 300: Host 400: Host accommodating router 500: Multicast relay router 610, 620: Distribution server

Claims (18)

An IP multicast switching control system having an IP multicast network, a host accommodating router connected to the IP multicast network, and a distribution server accommodating router,
The host accommodating router includes an IP multicast address, a plurality of source IP addresses corresponding to the IP multicast address, system information indicating whether each source IP address is a working system or a standby system, and each source IP address A switching control table for storing the reception state of the packet, means for selecting and outputting the multicast packet based on the source IP address among packets of the same IP multicast address, and means for monitoring the reception state of the multicast packet In the switching control table, only one source IP address among the source IP addresses of the same IP multicast address is stored as the active system, the other source IP address is stored as the standby system, and the multicast packet The means for monitoring the reception status is The information of the IP multicast address and the source IP address written in the IP header of the strike packet is acquired, and the combination of the IP multicast address and the source IP address is received or not received in the switching control table. If the active system stored in the switching control table has not been received for a predetermined time, the source IP address is switched to the standby system, and the source of the original standby system is Of the IP addresses, one of the source IP addresses being received is switched to the working system, and the means for selecting and outputting the multicast packet refers to the switching control table, and uses the working IP packet of the same IP multicast address. An IP multicast switching control system that outputs only a packet of a system transmission source IP address. In the IP multicast switching control system according to claim 1,
The switching control table stores the priority order of each source IP address instead of storing whether each source IP address is a working system or a standby system,
In the host accommodating router, the means for selecting and outputting the multicast packet refers to the switching control table, and only packets of the source IP address having the highest priority among receiving packets of the same IP multicast address are received. An IP multicast switching control system that outputs the IP multicast switching control system. In the IP multicast switching control system according to claim 1,
The host-accommodating router comprises means for selectively issuing a multicast participation request to an upstream device instead of means for selectively outputting the multicast packet;
In the host accommodating router, the means for selectively issuing the multicast participation request refers to the switching control table, issues a multicast participation request only to the source IP address of the active system, and receives the multicast packet. Means for monitoring the reception of the active system packet, and when the active system packet is not received within a predetermined time, the current system of the switching control table is switched to the standby system, In the standby control system, one source IP address is switched to the active system, and in the switching control table, when switching occurs, the means for selectively issuing the multicast participation request is multicast participation for the switched active system An IP multicast switching control system characterized by transmitting a request. The IP multicast switching control system according to claim 2,
The host accommodating router comprises means for selectively issuing a multicast participation request instead of means for selectively outputting the multicast packet;
In the host accommodating router, the means for monitoring the reception state of the multicast packet monitors the reception of the packet of the source IP address that issued the multicast participation request, and does not receive the packet within a predetermined fixed time. In the switching control table, the source IP address having the next highest priority is switched to the working system, and when switching occurs in the switching control table, means for selectively issuing the multicast participation request, An IP multicast switching control system, wherein a multicast participation request is transmitted to an active system after switching. In the IP multicast switching control system according to claim 4,
The host-accommodating router includes a timer, and when switching to a source IP address that issues a multicast participation request, if the priority of the source IP address before switching is the highest priority, the packet is sent to the packet of the source IP address before switching. On the other hand, when the timer is started and a predetermined time elapses, a multicast participation request is issued to the pre-switching source IP address, and a multicast participation request is issued when a packet of the pre-switching source IP address is received. An IP multicast switching control system, wherein a source IP address is returned to a source IP address before switching. In the IP multicast switching control system according to claim 4,
The host accommodating router includes a timer, and when the source IP address before switching is switched to the source IP address issuing the multicast participation request, if the priority is higher than the source IP address after switching, The timer is started for the packet of the source IP address before switching, and after a predetermined time elapses, a multicast participation request is issued to the source IP address before switching, and the packet of the source IP address before switching is received. In such a case, the IP multicast switching control system returns the source IP address that issues the multicast participation request to the source IP address before switching. The IP multicast switching control system according to claim 5,
The host-accommodating router includes means for selectively outputting multicast packets, and the means for monitoring the reception state of the multicast packets determines in advance the packets of the IP multicast address and the source IP address issuing the multicast participation request. If it is not received within a certain period of time, if the priority of the source IP address is the highest in the IP multicast address, the source IP address of the next priority in addition to the source IP address When the means for monitoring the reception of the multicast packet receives a multicast packet of a plurality of source IP addresses for the same IP multicast address, the multicast packet is selectively output. Means to An IP multicast switching control system which selectively outputs a packet having the highest priority among transmission source IP addresses of received packets and stops a multicast participation request for a transmission source IP address having a priority other than the highest priority . The IP multicast switching control system according to claim 6,
The host-accommodating router includes means for selectively outputting a multicast packet, and if the source IP address before switching is higher in priority than the source IP address after switching, the source IP address before switching and after switching When the means for issuing a multicast participation request to a source IP address and monitoring the reception of the multicast packet receives multicast packets of a plurality of source IP addresses for the same IP multicast address, the multicast packet Means for selecting and outputting only the packet with the highest priority among the source IP addresses of the received packets, and transmitting with a priority other than the highest among the source IP addresses of the received packets Stop the multicast participation request for the original IP address IP Multicast switching control system according to claim.   An IP multicast switching control system comprising the IP multicast switching control system according to claim 1 and the IP multicast switching control system according to claim 3 in combination.   An IP multicast switching control system comprising: the IP multicast switching control system according to claim 2; and the IP multicast switching control system according to any one of claims 4 to 8. In the IP multicast switching control system according to any one of claims 3 to 8,
When the host accommodating router receives a multicast participation request designating an IP multicast address and a source IP address from the host, the priority order among the receiving is within the range of the source IP address designated by the host. An IP multicast switching control system that outputs only a packet having the highest source IP address. In the IP multicast switching control system according to any one of claims 1, 2, 9, or 10,
The means for selectively outputting the multicast packet uses a packet filter provided in the packet receiver to transfer and set only the combination of the output IP multicast address and the source IP address, and the other IP multicast address and source IP address An IP multicast switching control system characterized in that a combination of the above is set as a cutoff setting. An IP multicast network, a host accommodating router and a distribution server accommodating router connected to the IP multicast network, and the host accommodating router includes an IP multicast address, a plurality of source IP addresses corresponding to the IP multicast address, A switching control table that stores system information indicating whether each source IP address is a working system or a standby system, and a reception state of a packet of each source IP address, and a source of the packets of the same IP multicast address An IP multicast switching control method in an IP multicast switching control system comprising means for selectively outputting a multicast packet based on an IP address and means for monitoring the reception state of the multicast packet,
Storing, in the switching control table, only one source IP address among the source IP addresses of the same IP multicast address as the active system, and storing the other source IP address as the standby system, and the multicast packet Means for monitoring the reception state of the IP multicast address and the source IP address recorded in the IP header of the received multicast packet and acquiring the IP multicast address and the source IP address in the switching control table The combination of whether the combination is being received or not received, and the active system stored in the switching control table has not been received for a predetermined time, the transmission source The IP address is switched to the standby system, and the source IP address being received among the source IP addresses of the original standby system The step of switching one of the addresses to the working system and the means for selectively outputting the multicast packet refer to the switching control table, and only packets of the working source IP address among packets of the same IP multicast address are referred to. An IP multicast switching control method comprising: an output step. The IP multicast switching control method according to claim 13,
The switching control table stores the priority order of each source IP address instead of storing whether each source IP address is an active system or a standby system;
The means for selectively outputting the multicast packet of the host accommodating router refers to the switching control table and outputs only the packet of the source IP address having the highest priority among the packets of the same IP multicast address being received. An IP multicast switching control method comprising the steps of: The IP multicast switching control method according to claim 13,
The host-accommodating router comprises means for selectively issuing a multicast participation request to an upstream device instead of means for selectively outputting the multicast packet;
Means for selectively issuing the multicast participation request refers to the switching control table, and issues the multicast participation request only to the working source IP address; and means for monitoring the reception state of the multicast packet Monitors the reception of the active system packet, and when the active system packet is no longer received within a predetermined time, the active system of the switching control table is switched to the standby system, and the original standby system A step of switching one of the transmission source IP addresses to the active system, and means for selectively issuing the multicast participation request when switching occurs in the switching control table, the multicast participation request to the active system after switching An IP multicast switching control method comprising a step of transmitting. The IP multicast switching control method according to claim 14, wherein
The host accommodating router comprises means for selectively issuing a multicast participation request instead of means for selectively outputting the multicast packet;
The means for monitoring the reception state of the multicast packet monitors the reception of the packet of the source IP address that issued the multicast participation request, and when the packet is not received within a predetermined time, the switching control In the table, the step of switching the source IP address having the next highest priority to the active system, and means for selectively issuing the multicast participation request when switching occurs in the switching control table, An IP multicast switching control method comprising a step of transmitting a multicast participation request to a system. An IP multicast network, an IP multicast address connected to the IP multicast network, a plurality of source IP addresses corresponding to the IP multicast address, and system information indicating whether each source IP address is a working system or a standby system , And a host accommodating router having a switching control table for storing a reception state of a packet of each source IP address, and an IP multicast switching control system comprising a distribution server accommodating router connected to the IP multicast network. An IP multicast switching control program executed by the accommodating router,
Processing for storing only one source IP address as the active system and storing other source IP addresses as the standby system among the source IP addresses of the same IP multicast address in the switching control table, received multicast packets Information of the IP multicast address and the transmission source IP address described in the IP header is acquired, and whether the combination of the IP multicast address and the transmission source IP address is being received or not received in the switching control table. If the active system stored in the switching control table has not been received for a predetermined time, the source IP address is switched to the standby system, and the source IP address of the original standby system is switched. A process of switching one of the currently received source IP addresses to the active system, and the switching control table Irradiation and, among the same IP multicast address packet, a process of outputting only packets of the primary system transmission source IP address, IP multicast switching control program instructs the host receiving router.   18. A computer-readable recording medium on which the IP multicast switching control program according to claim 17 is recorded.

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